Abstract:Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) belongs to the lighttolerant coniferous species of Cunninghamia family,which is widely distributed in China and Vietnam. It has a series of characteristics including fast growth,high yield,beautiful wood grain,insect resistance (such as termites),corrosion resistance,and adaptability to arid and arid habitats. It is one of the important endemic fastgrowing timber species in China. In order to solve the decline of soil quality in Chinese fir plantations and the problem of soil fertility decline,effects of fertilization and litter addition on soil nutrient and soil microbial properties of Chinese fir plantation in Central South Jiangxi Province were studied by using the bag method to set up different fertilization treatments and litters of multiple tree species combined treatments. The results showed that compared with the control (without fertilization) treatment, the content of soil alkline nitrogen and available phosphorus of mixed N + P fertilizers treatment in the Chinese fir plantation soil increased by 10.7% and 36.7%, respectively, which was significantly higher than that of the single fertilizer treatment. Compared with the control (without addition of litters) treatment,mixed addition of litters of C. lanceolata+P. bournei and single addition of P. bournei litter promoted soil microbial biomass significantly,indicating that the litter of P. bournei played a key role in decomposing the mixed litter of Chinese fir plantation. In practice,the mixed forest of C. lanceolata × broadleaved is recommended,and the current young to mid age pure C. lanceolata stand should be reformed by means of closetonature transformation in order to change the composition,quality and quantity of litter. In this way,the additive effect of decomposing mixed litter of multiple tree species can be fully used and the soil nutrient status of the Chinese fir plantation can be improved by combining with the application of mixed N+P fertilizers.